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Does the time machine work in sleep mode?

Does the time machine work in sleep mode

Time Machine does it backup every hour, day, week, etc but if the backup is up to date, for example only 1 minute ago and I create a document and save it to the desktop or a folder, then put the Mac to sleep mode and not return to the computer for at least 2 hours will Time Machine backup the document/ folder in about 1 hour’s time. Or does it commence the backup only when I wake up the computer?

there’s not much point in running a Time Machine backup when you haven’t been using the computer: if you’re not using it, nothing has changed, so there’s nothing new to back up.

So, Does the time machine work in sleep mode? Let’s find out…

Does the time machine work in sleep mode?

Yes. Time Machine will work during sleep. A lot of things will work during sleep. This feature is called Power Nap. If your Mac supports Power Nap it can perform Time Machine backups while it’s asleep or the lid is shut. It just needs to be plugged into the mains.

You can find Power Nap in System Preferences > Energy Saver.

Choose Enable Power Nap while plugged into a power adaptor if it’s not already selected under Power Adapter.

What is “Power Nap”?

Power Nap allows your Mac to perform useful activities while it’s asleep (there are plenty of activities that it will do but the important one we’d like to focus on today is the Time Machine backup).

How to get Time Machine to work during Power Nap

  • On your laptop, choose Apple menu (the black apple on the top left corner) > System Preferences, then click Energy Saver.
  • Check the box beside “Enable Power Nap while on battery power” and you’re done.

You obviously need to ensure it’s plugged into power but otherwise, plug the external hard drive you use with Time Machine for backups and you can fold down your laptop and let it backup overnight.

This way, you will have a nightly backup of your Mac without the need to remember to plug it during the day.

Time Machine backup hasn’t made any progress. Even the hard drive light is out while the machine sleeps.

Energy saver is at the default setting of sleep after 15 minutes and Enable Power Nap is checked.

It just doesn’t seem to work. Are my expectations wrong? Shouldn’t it just back up while in “sleep” mode?

This is a newly re-installed OS with no special apps installed and no custom software besides MS Office.

Will a Scheduled Backup Wake My Machine Up If It’s Sleeping?

Some backup programs can wake up a sleeping machine, but there are still things that could go wrong and cause a backup to fail.

If my computer is scheduled to back up my files on, for instance, Saturday night, and it’s sleeping, does the backup still occur? I received a warning that my backup was not successful: “The request could not be performed because of an I/O device error.” I’m backing up to a Western Digital external hard drive.

The short answer is: probably not.

But that answer doesn’t relate to the error message you’re seeing.

Scheduled backups

First, let me say: “Good on you for backing up!” Unfortunately, you’re still in the minority as we try to get more and more people to back up.

As I said, the short answer to your question is typically “no.” If your computer is sleeping, you cannot be guaranteed that the backup program will cause the system to wake up.

And waking up is exactly what it needs to do for the backup to process. Your machine must be running for a backup to happen.

Automatic wake-up

Some backup programs include an option that claims to wake your computer in order to run the backup.

There are several problems, however:

Not all backup programs have this option.

The option may wake from Sleep, but not from Hibernate. If your machine is in Hibernate because it was in Sleep for too long, your backup will likely not run.

If your machine is on battery — the most common scenario when using Sleep and/or Hibernate — the battery may run out before any backup has completed.

The only reliable option is to run the backup the next time the machine is powered on if a scheduled backup was missed. Once again, not all backup programs include such an option.

I/O device error

The error you’re seeing may or may not be related to attempting to run the backup immediately after waking up.

In my opinion, it’s more likely the error is an unrelated error accessing the drive.

Try a manual backup to see if that’s the case. If it works, my guess is that the scenario is playing out like this:

Your external hard drive has stopped spinning to save power – either because the system went to sleep, or the drive itself spins down after some period of inactivity.

The backup program starts and begins to access the external hard drive.

The drive “wakes up” and begins spinning.

The drive takes too long to be ready, and the computer or backup program declares the error.

When the backup program tries to access that external hard drive, it’s just not ready.

Solution 1: leave your computer running

I don’t know of a good solution in these situations, other than leaving your computer on.

That’s what I do. My computers run 24 hours a day, in part so scheduled activities such as backups can run in the middle of the night, when I’m not using the system.

Solution 2: run missed backups on the login

As I mentioned earlier, in some backup programs there are options to automatically run any missed back up the next time you power on or log in to the machine.

The downside is, depending on the backup software you’re running, your machine may seem more sluggish while the backup proceeds.

But the benefit is that you’ll have a backup.

Solution 3: choose a different time

You can avoid the problem completely by choosing a backup time you know your computer will be up and running — perhaps during a daily lunch break or other time when the impact of a running backup won’t be as noticeable.

This Article is Updated.

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Robert Smith

Robert Smith is a technology lover and loves to write about laptops, monitors, printers, tablets, Apple products and anything that's related to computers and games. He is passionate enough that he maintains this blog regarding tech updates on a daily basis.